/*[INCLUDE-IF CRAC_SUPPORT]*/
/*
 * Copyright IBM Corp. and others 2024
 *
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which accompanies this
 * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
 * or the Apache License, Version 2.0 which accompanies this distribution and
 * is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * This Source Code may also be made available under the following
 * Secondary Licenses when the conditions for such availability set
 * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
 * General Public License, version 2 with the GNU Classpath
 * Exception [1] and GNU General Public License, version 2 with the
 * OpenJDK Assembly Exception [2].
 *
 * [1] https://www.gnu.org/software/classpath/license.html
 * [2] https://openjdk.org/legal/assembly-exception.html
 *
 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
 */
package jdk.crac.management;

import java.util.concurrent.TimeUnit;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectName;
import openj9.internal.criu.InternalCRIUSupport;

/**
 * An implementation of the CRaCMXBean interface.
 */
public class CRaCMXBeanImpl implements CRaCMXBean {
    private final static CRaCMXBean INSTANCE = createInstance();

    private CRaCMXBeanImpl() {
    }

    private static CRaCMXBeanImpl createInstance() {
        return new CRaCMXBeanImpl();
    }

    /**
     * Returns an instance of {@link CRaCMXBeanImpl}.
     *
     * @return an instance of {@link CRaCMXBeanImpl}.
     */
    public static CRaCMXBean getInstance() {
        return INSTANCE;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public long getUptimeSinceRestore() {
        long restoreTime = getRestoreTime();
        return (restoreTime > 0) ? (System.currentTimeMillis() - restoreTime) : -1;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public long getRestoreTime() {
        long processRestoreStartTime = InternalCRIUSupport.getProcessRestoreStartTime();
        return (processRestoreStartTime > 0) ? TimeUnit.NANOSECONDS.toMillis(processRestoreStartTime) : -1;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public ObjectName getObjectName() {
        try {
            return ObjectName.getInstance(CRAC_MXBEAN_NAME);
        } catch (MalformedObjectNameException e) {
            throw new InternalError(e);
        }
    }
}
